Variable loudness alarm mechanism

ABSTRACT

A MECHANISM FOR ADJUSTING THE LOUDNESS OF AN ALARM FROM THE FRONT OF AN ALARM CLOCK WHEREIN A SLIDER HAVING A RACK INTEGRALLY FORMED THEREON IS LOCATED BETWEEN A FRONT MOUNTING PLATE AND A FRONT WALL OF THE CLOCK CASING. AN ACTUATING LEVER INTEGRALLY FORMED WITH THE SLIDER EXTENDS THROUGH THE FRONT WALL OF THE CASING SO THAT THE VOLUME OF THE ALARM MAY BE ADJUSTED BY SIMPLY SLIDING THE ACTUATING LEVER BACK AND FORTH ACROSS THE FRONT WALL OF THE CLOCK.

Feb. 2, 1971 GM GLER 3559,31;-

VARIABLE'LOUDNESS ALARM MECHANISM Filed Feb. 28, 1969 v o l 0 Mil William C. Wing\er.

b I 5 Attorney United States Patent 3,559,396 VARIABLE LOUDNESS ALARM MECHANISM William C. Wingler, Stow, Mass, assignor to General Electric Company, a corporation of New York Filed Feb. 28, 1969, Ser. No. 803,355 Int. Cl. G04b 23/10 US. Cl. 58--21.12 4 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION This invention relates to a mechanism for varying the loudness of an alarm of an alarm clock, and more particularly, to. a unique slider construction for adjusting the loudness of the alarm from the front of the clock.

In United States Letters Patent No. 3,251,182, May 17, 1966 to Marble, assigned to the same assignee as the present invention, there is disclosed a mechanism for varying the loudness of an electromagnetic vibrator alarm of an alarm clock. As shown and described in the patent, a coin slot control knob protrudes from the rear of the clock for adjusting the loudness of the alarm mechanism. Within the clock, a control spring is arranged to exert a variable force on a vibrator alarm, and a cam and lever mechanism is arranged for transmitting motion of the control knob to the control spring to adjust the loudness of the alarm. It is desirable that the mechanism for adjusting and setting of the loudnes of the alarm be accessible from the front of the clock and also be visible from the front of the clock. It is also desirable to provide a front control mechanism which may be manufactured at relatively low cost and be compactly arranged so that it may be incorporated in an alarm clock without increasing the size of the clock casing.

SUMMARY OF THE INVENTION Accordingly, it is a primary object of this invention to provide an improved variable loudness alarm mechanism for an electric clock having a minimum number of parts which may be readily manufactured and assembled to each other, and which may be readily and conveniently adjusted from the front of a clock.

In accordance with one of the aspects of this invention, a mounting plate of the alarm clock is formed with an elongated slot, a front casing wall of the clock is also provided with a slot, and a unique slider is located between the front mounting plate and the front casing wall. The elongated slider includes an integrally formed fiat guide wall, an integrally formed toothed rack extending rearwardly from the guide wall and an integrally formed actuating lever extending forwardly from the guide wall. The slider is positioned on the clock so that the guide wall is located between the front mounting plate and the front casing wall, the rack extends behind the mounting plate, and the actuating lever extends forwardly in front of the front casing wall. Gear means extends from the toothed rack to the means for adjusting the spring. With this arrangement, the forwardly extending actuating lever may be manually adjusted at the front of the clock for adjusting the spring and the loudness of the alarm.

3,559,396 Patented Feb. 2., 1971 Accordingly, a very simple, yet effective arrangement for controlling the loudness of the alarm by reciprocating a lever at the front of the clock is achieved.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and attendant advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing in which:

FIG. 1 is a front perspective view of an electric clock incorporating the variable loudness alarm mechanism of this invention;

FIG. 2 is a side elevational view of the electric clock with the casing partially removed;

FIG. 3 is an exploded view of the principal components of the variable loudness alarm mechanism and the vibrator of the alarm; and

FIG. 4 is a front elevational view of the clock mounting plate.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing and first particularly to FIG. 1, there is shown an electric clock 2 comprising a plastic casing 4 having an open front which is closed by a transparent front casing crystal wall 6 making visible a dial face *8 located behind the front casing wall.

As shown in FIG. 2, the clock mechanism comprises a supporting structure including a base plate 10 and a front mounting plate 12 spaced from the base plate and arranged generally parallel thereto for supporting the clock mechanism. conventionally, the base plate 10 and front mounting plate 12 are maintained in spaced relation by a number of studs and spacer posts including those indicated at 14. The clock is provided with hour, minute and second hands 16, 18 and 20, respectively, driven by a plurality of concentric shafts which extend through a center stack bushing 22 which is attached to the front mounting plate 12.

The timing device may include any suitable form of timer motor, here shown as a self-starting synchronous motor 24, a field coil 26 of which is connected to a source of regulated frequency alternating current. A resilient magnetic vibrator 28 operated by leakage flux from the motor is arranged to have its free end portion 30 vibrate against a stator 32 and produce an audible signal at all times when the motor is energized unless the vibrator is prevented from vibrating by a lever 34.

As is known in the art, it is possible to vary the loudness of an electromagnetic vibrator by varying the air gap between the vibrator 28 and the stationary member 32 which it strikes. As shown more particularly in FIG. 3, an adjustable spring 36 is provided for varying the air gap and simultaneously the stiffness of the vibrator 28 to thereby vary the loudness of the alarm. A lever 38 is pivotally supported by a pin 40. Rotation of a cam 42 in an aperture 44 in the lever causes rotation of the lever 38 about the pin 40. The free end of the lever 38 includes a spring engaging means 46 which may be a tab 48 bent at right angles to the lever with a hole formed therein to receive one end of the spring 36. Spring 36 includes a convolute section 50 which is placed over a spacer post. The spring 36 has arms of unequal length. The shorter arm 52 is connected to the spring engaging means 46, 48 of the lever while portion 54 of the longer arm 56 of the spring is positioned to engage the top surface of vibrator 28.

Rotation of the cam 42 in a clockwise direction causes the lever 38 to be pivoted counter clockwise, thereby rotating the short arm 52 of the said spring 36 in a clockwise direction. Clockwise rotation of the spring 36 brings portion 54 of the longer arm 56 of the spring into engagement with the top surface of the vibrator 28 to soften or lower the volume of the alarm.

Until the portion 54 of the spring engages the vibrator, the lever system comprising the cam 42, the lever 38 and the spring 36 has a large mechanical ratio such as 18 to 1. This large ratio results from positioning the aperture 44 closer to pin 40 than the spring engaging means 46, 48 and by making the spring arm 52 shorter than the spring arm 56. Slight rotation of the cam 42 will effect a relatively large movement of the portion 54 of the longer arm 56 of the spring. Even though the mechanical tolerances of the dimensions and positions of the alarm mechanism components are large, it is possible to compensate for these large tolerances by bringing the portion-54 of the longer spring arm 56 into contact with the vibrator 28 by a very slight rotation of the cam 42.

In accordance with my invention, a unique mechanism is provided for adjusting the position of cam 42 from the front of the alarm clock in order to vary the loudness of the alarm. As shown more particularly in FIG. 3, a pinion gear 60 is fixed to cam 42 so that rotation of the pinion gear will cause corresponding rotation of the cam 42 and an integrally formed rocker lever and sector gear construction 62 is provided for causing rotation of the pinion gear 60. As illustrated, rocker lever 62 is pivoted to the base plate of the clock by a pivot pin 64, a sector gear 66 is formed at one end of the rocker for cooperating with pinion gear 60, and a sector gear 68 is formed at the other end of the rocker for cooperating with a pinion gear 70. Preferably, pinion gear 70 and a larger gear 72 are integrally formed of plastic material and are suitably mounted between base plate 10 and front plate 12.

In accordance with my invention, an integrally formed rack and slider 74 is provided for moving gear 72 and gear train members 70, 68, 66 and 60 for adjusting spring 52 to adjust the loudness of the alarm. With this construction, it can be appreciated that movement of the rack slider 74 to the right as shown in FIG. 3 will cause counter clockwise rotation of gear 72 and pinion 70, clockwise rotation of rocker 62 and sector gears 68 and 66, clockwise rotation of pinion 60 and cam 42 to cause lever 38 to be pivoted counter clockwise thereby rotating the spring 36 in a clockwise direction to bring the longer arm 56 of the spring into engagement with the top surface of the vibrator 28 to soften or lower the volume of the alarm. As shown more particularly in FIG. 3, my unique rack slider 74 which is preferably formed of plastic or other suitable material includes a plurality of rack teeth 76 for meshing with gear 72, and an integrally formed control lever 78 which extends through the front wall 6 of the clock for permitting manual setting of the slider.

A unique arrangement is provided for mounting and guiding the slider on the clock. As shown, the slider includes a generally vertical front guide wall 80, a generally horizontal central guide portion 82, two upwardly and downwardly extending rear guide tabs 84 and 85, respectively, formed at the right side of the slider, and an up wardly extending guide tab 86 formed at the left side of the slider. As shown more particularly in FIG. 4, an elongated slot 88 is formed in the front mounting plate 12 of the clock for receiving and mounting slider 74. The slot 88 includes upwardly and downwardly extending notches 90 and 92 which correspond to the upwardly and downwardly extending tabs 84 and 85 on the slider and an upwardly extending notch 94 which corresponds to the upwardly extending rear guide tab 86 of the slider. With this construction, the slider 74 may be readily assembled to the clock without the use of separate fastening devices. With reference to FIGS. 3 and 4, the slider 74 is simply aligned with the slot 88 so that tabs 84 and 85 are in line with notches 90 and 92, and tab 86 is in line with notch 94. Then, the slider may be pushed rearwardly to'position the tabs 84 and 86 behind front mounting plate 12, as illustrated in FIG. 2. Movement of the slider to the right, as illustrated in FIG. 4, causes the tabs 84, 85 and 86 to slide on the rear surface of mounting plate 12 to thereby hold the slider on the front plate 12 of the clock. It can be appreciated that the rear surface of the front guide wall slides on the front surface of front mounting plate 12, the front surfaces of tabs 84 and 86 slide on the rear surface of mounting plate 12, and the top and bottom surfaces 81 and 83, respectively, of the central guide portion 82 slide on the upper and lower inner surfaces 87 and 89, respectively, of the wall which forms the slot 88.

In order to complete the assembly of the clock, a slot- 96 is formed in the bottom portion 98 of the front wall 6 of the clock casing for receiving control lever 78 of the slider 74. The upper portion of the crystal wall 6 is preferably made of transparent material so that the clock indicia may be readily viewed, and the lower portion 98 of the front wall is preferably painted so that the internal mechanism of the clock cannot be seen from the front of the clock. While the slot 96 which receives the control member 78 is made long enough to permit a full range of adjustments to the variable loudnessalarm mechanism the left end 97 of the slot 96 is related to the left end of the slot 88 and notches 90, 92 and 94 so that upon movement of the control lever 78 to the left as viewed in FIG. 1, the lever 78 will abut the end 97 of slot 96 before tabs 84, and 86 become in line with the notches 90, 92 and 94 in the front mounting plate 12. Thus, the slider 74 is retained on the front mounting plate.

OPERATION If it is desired to soften or lower the volume of the alarm, it is merely necessary to touch the manually ad justable lever 78 which protrudes from the front of the clock and move it a slight distance to the right. Such movement will cause rightward movement of the rack 76, counter clockwise movement of gears 72 and 70, clockwise movement of rocker 62 and gears 68 and 66, clockwise movement of pinion gear 60 and cam 42 to cause counter clockwise movement of lever 38 which, in turn, causes clockwise movement of spring 36 thereby increasing the force of spring 36 on the vibrator arm 28 to soften the alarm. Conversely, should it be desired to increase the volume of the alarm and make it louder, it is merely necessary to touch the control lever 78 and move it a slight distance to the left as shown in FIG. 3. During such movement, the gear train 72, 70, 68, 66, 58 will pivot spring 36 counter clockwise to lessen the force of spring 36 on vibrator 28 thereby making the alarm louder. Accordingly, the loudness of the alarm may be conveniently set from the front of the clock and after having been set the relative loudness of the alarm will be indicated to the user by simply looking at the front of the clock and observing the relative position of the control lever 78 with respect to the front of the clock and the slot 96 within which it travels.

From the foregoing description, it will be appreciated that my improved variable loudness alarm mechanism which may be adjusted from the front of the clock includes a minimum number of relatively easily manufactured parts. The integrally formed rocker lever 66 and sector gears 66 and 68 may be formed in a simple casting operation. Likewise, the gear and pinion 70, 72 may be integrally molded with each other. The unique slider member 74 may be molded of a suitable plastic material, and as previously described may be readily and conveniently connected to the clock without the use of tools or a single piece of fastening hardware. Thus, an exceedingly simple yet sturdily constructed mechanism for loudness of the alarm; a mechanism manually movable from the front of the alarm clock for adjusting the spring to vary the loudness of the alarm comprising:

(a) a mounting plate having an elongated slot formed therein;

(b) a front casing wall having a slot formed therein;

and

(c) an elongated slider including an integrally formed generally flat guide wall, an integrally formed toothed rack extending rearwardly from said guide wall, and an integrally formed actuating lever extending forwardly from said guide wall, said slider being positioned on said clock with said guide wall being located betwen said front mounting plate and said front casing wall, said rack extending behind said mounting plate and said actuating lever extending in front of said front casing wall; and

(d) gear means extending from said toothed rack to the means for adjusting the spring so that the loudness of the alarm may be adjusted by manually adjusting the position of said actuating lever at the front of the clock.

2. In a variable loudness alarm mechanism for use with an alarm clock including a vibrator for sounding an alarm, a spring engaging said vibrator, and an adjustable means to eifect movement of the spring to vary the loudness of the alarm; a mechanism manually movable from the front of the alarm clock for adjusting the spring to vary the loudness of the alarm comprising:

(a) a mounting plate having an elongated slot formed therein, said slot including upwardly and downwardly extending notches;

(b) a front casing wall having a slot formed therein;

(c) an elongated slider including an integrally formed generally fiat guide wall, a central guide portion extending rearwardly from said guide wall, an integrally formed toothed rack extending rearwardly from said guide wall, and integrally formed upwardly and downwardly extending tabs located behind said front guide wall, so that said slider may be positioned on said front mounting plate by inserting said upwardly and downwardly extending tabs within said upwardly and downwardly extending notches and then sliding the slider with respect to said front plate so that the front plate is positioned between the front guide wall of the slider and the upwardly and downwardly extending tabs; and

((1) gear means extending from said toothed rack to the means for adjusting the spring so that the loudness of the alarm may be adjusted by manually adjusting the position of said actuating lever at the front of the clock.

3. A variable loudness alarm mechanism as defined in claim 2 wherein said elongated slider includes an integrally formed control lever extending forwardly from said central guide portion, said control lever extending through the slot formed in the front casing wall and being arranged with respect to said slot so that it will abut the end of the slot before the tabs formed on said slider become in line with the notches formed in said mounting plate so that the slider is retained on the front mounting plate when the parts are in their assembled position.

4. In a variable loudness alarm mechanism for use with an alarm clock including a vibrator for sounding an alarm, a spring engaging said vibrator, and an adjustable cam for moving lever to effect movement of the spring to vary the loudness of the alarm; a mechanism adjustable from the front of the alarm clock for effecting movement of the lever and the spring to vary the loudness of the alarm comprising:

(a) a pinion gear fixed to said cam for adjusting the position of said cam;

(b) a pivoted rocker lever having sector gears formed at opposite ends thereof, one of said sector gears being in mesh with said pinion;

(c) an integrally formed gear and pinion, said gear and pinion being formed of the same material and being concentric with each other, said pinion being in mesh with said other sector gear,

(d) an elongated slider having a plurality of rack teeth formed thereon, the teeth of said rack being in mesh with said gear; and

(e) an actuating lever integrally formed with said slider, said actuating lever extending through a front wall of said alarm clock whereby the loudness of the alarm may be adjusted by simply moving the slidable adjustable lever back and forth across the front wall of the clock.

References Cited UNITED STATES PATENTS 1,691,081 11/1928 Pierce 582l.12 1,907,282 5/1933 Waldheim 582l.l2 2,003,785 6/1935 Ingraham 5821.l2 2,506,379 5/1950 Muchow 58--2l.12 3,251,182 5/1966 Marble 5821.12 3,328,952 7/1967 Clark 5821.12

STEPHEN J. TOMSKY, Primary Examiner L. R. FRANKLIN, Assistant Examiner 

